net/hns3: fix dumping VF register information

net/hns3: fix dumping VF register information

Currently, when the API interface named rte_eth_dev_get_reg_info is
called by upper applications based on VF device, it returns error.

We can read registers directly to get ring and interrupt related
information in hns3 PF/VF PMD driver. But for some other internal table
entries and common configuration information, we can get them only
through the command interface between driver and firmware in PF driver,
and VF driver has not the related access permission.

This patch fixes it by preventing getting these information through the
command interface based on VF device in 'get_reg' ops implementation
function.

Fixes: 936eda25e8da ("net/hns3: support dump register")
Cc: stable@dpdk.org
Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Wei Hu (Xavier) <xavier.huwei@huawei.com>